Gently toss chicken breast slices with the first measures of light
soy sauce, Shao hsing wine and cornstarch, and allow to marinate at
least twenty minutes. Heat wok on high heat until a thin ribbon of smoke spirals up from
the hot metal. Add peanut or canola oil, and let it heat for thirty
seconds. Add the bacon, and stir well to separate each piece out from
the others. Cook, stirring, until the bacon has rendered its fat and is done but not crispy. Remove from the wok and set aside. To the wok add the chicken, spreading it out into a single layer
against the bottom of the wok. Sprinkle with the sugar, garlic, ginger
and scallion slices. Leave the chicken undisturbed for a minute or so,
until the bottom of the chicken begins to brown, then cook, stirring
until 2/3 of the chicken is no longer pink, but white and brown.
Sprinkle the chicken with the soy sauce, wine and vinegar and stir,
scraping up any browned bits from the bottom and sides of the wok. Add
the bacon back to the wok. Add the bok choy and the broth or stock and cook, stirring, and
scraping any more browned bits from the bottom of the wok, until the bok
choy wilts slightly and a sauce forms. Sprinkle with the scallion tops, drizzle with sesame oil, and give
the whole thing a final stir before scraping it out of the wok into a
warmed serving. Serve with steamed rice and really good Chinese tea.